application of cellulase enzyeme in textile processing by shaikh

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A Project on

Application of cellulase enzyme on textile Processing

Submitted by:

Name ID

Arup Chandra Roy 072-178-041

Md. Iqbal Shaikh 072-223-041

Mehedi Hasan Khan 072-224-041

Abu Sayed 072-226-041

Gm. Mortuza 073-050-741

Md. Asadul Islam 081-028-741

Md. Sharif Miah 081-118-041

Sufal Chandra Sutradhar 081-272-041

Md.Abdus Sobahan 081-279-041

Supervisor:

Md. Mahbub Hasan

Sr. Lecturer , department of textile Engineering

Primeasia University

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Adessertation submmited on: “Application of cellulase enzyme on textile Processing” To the department of Textile engineering in partial fulfillment of the

credit requirement for achiving the Bachalor Degree in textile

engineering by PRIMEASIA UNVERSITY.

Submitted by:

Name ID

Arup Chandra Roy 072-178-041

Md. Iqbal Shaikh 072-223-041

Mehedi Hasan Khan 072-224-041

Abu Sayed 072-226-041

Gm. Mortuza 073-050-741

Md. Asadul Islam 081-028-741

Md. Sharif Miah 081-118-041

Sufal Chandra Sutradhar 081-272-041

Md.Abdus Sobahan 081-279-041

Supervisor:

Md. Mahbub Hasan

Sr. Lecturer , department of textile Engineering

Primeasia University

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“Application of Cellulase enzyme on textile processing”

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By the name of Allmighty ALLAH;

The most gracious;

The most merciful;

The lord of all creation.

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To our Parents

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Acknowledgement

We would like to express our gratitude to all those who gave us the

possibility to complete this project.

We want to thank the department of textile engineering for giving the

permission to commence the project at first instance, to do the necessary research

work and to use departmental data. We have further more to thank the supervising

teacher Md. Mahabub Hasan, Sr. lecturer of textile Engg. Dept. who gave and

confirmed this permission and encourage us to go ahead with our project.

We are deeply indebted to Rahamot Group of Industries Limited, Hams

Fashions Limited, Jamuna Group of Industries Limited, Fakir Knitwear

Limited, Graphics Textiles Limited, BASF Chemicals Limited and Hotapara

Garments Limited for their help and co-operation and also to the Primeasia

University faculties. Their help, stimulating, suggestions and encouragement

helped us in all the time for this research and for writing the project.

At last all the credits go to Almighty Allah, who enabled us to complete the

project.

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Abstract

Now a day’s the whole universe is concern about the hygiene and they are

looking for eco-friendly processes every where. Textile processing is one of the

most pollutants responsible for polluting the environment at a large degree. Use of

Cellulase enzyme for denim washing & Bio-polishing of knit fabric is a standard

eco-friendly technique to achieve desired appearance and washing of denim and

also the desired appearance of the knit fabric. Applications of enzymes to replace

harsh chemicals and other difficulties for process industries have been practiced for

decades. In this study we have tried to observe the washing effect of denim fabric

and the bio-polishing effect of knit fabric with Cellulase enzyme under different

conditions.

This work also evaluates the effect of cellulase finishing of dyed cotton fabrics.

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Objectives of the Project:

The technology which is used to modify the appearance, out

look, comfortability & fashion of the garments is called garment

washing.

To know the effect of Cellulase enzyme on fabric or

garments after fabric or garments washing.

To find out the washing technique by which faded/old

look effect is created in the garments.

To create wash look appearance by cellulase washing of

garments. After washing the garments create a new look

which seems the new touch of fashion.

To produce soft garments by enzyme washing then it

seems to best touch of garments.

To attract the customers/Buyer by different types of

Fashionable washing and market developments.

To produce shrinkage free garments by enzyme washing.

To remove dirt, dust, spot by enzyme washing and create

new wash down appearance at the same time.

To obtain the best Bio-polishing effect on the knit fabric.

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Scope:

Enzyme wash is suitable for all cotton/ denim garments,

cellulosic woven or knitted and regenerated cellulosic like tencel and modal etc.

Permanent faded, soft hand effect can be produced on the

treated material.

It facilitates the removal of dead / immature cotton and

reduction of any fibre hairs on the surface (fewer

tendencies to pilling).

Faded look or wash-down look can be produced on treated material.

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Limitations:

Possibility of producing same effect is difficult.

Possibility of fabric damages during washing.

Application of cellulase enzyme in the textile processing

often results in a certain amount of loss of tensile strength

along with the desired performance.

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METHODOLOGY:

PRIMARY STAGES:

Visited to different washing Industries and knit dyeing industries

↓ Observed Different processes of denim washing (cellulase

enzyme) and Bio-polishing ↓

Observed the effect of enzyme on fabric and garments. ↓

Collected the Samples ↓

Group discussion done ↓

Selected the suitable Process and Recipe of Enzyme application on Textile Processing

SECONDARY STAGES:

Informations Collected from:

Books, internet

Visiting industries

Magazine

Seminar

And Completed

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content

Chapter -1

Garments washing --------------------------------------------------------- 16

Types of washing --------------------------------------------------------- 17

Chapter-2

Enzyme ---------------------------------------------------------- 18-19

Etymology and history ----------------------------------------------------- 20

Enzymes are specific and work in mild conditions -------------------- 21

Sources of enzymes -------------------------------------------------------- 22

Different type of enzymes ------------------------------------------------ 23-24

Types of machines used in garments washing plant ------------------- 25-31

Chapter-3

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Cellulase wash ----------------------------------------------------------------- 32-34

Cellulase enzyme processing -------------------------------------------- 35-36

Process sequences of enzyme wash (for dark shade) ----------------- 37-47

Enzyme wash process (for light shade) -------------------------------- 48-51

Stone enzyme wash ------------------------------------------------------ 52-55

Enzyme inactivation ----------------------------------------------------- 56

Advantage of enzyme washing ----------------------------------------- 57

Chapter-4

Bio-polishing of knit fabric --------------------------------------------- 58-59

Mechanism of bio-finishing -------------------------------------------- 60-61

Bio-polishing of knit fabric with cellulase enzyme ------------------ 62

Favorable conditions of enzyme for bio-finishing ------------------- 63

Procedure of bio-polishing of knit fabric ------------------------------ 64-67

Advantages of using enzymes for bio-polishing are ----------------- 68

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Cellulase enzyme offers the following benefits ---------------------- 69

Requirement of enzyme wash ------------------------------------------ 70

Conclusion ----------------------------------------------------------------

71

_____________

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Chapter-1

GARMENTS WASHING:

The technology which is used to modify the appearance, out look, comfortability

& fashion of the garments is called garment washing.

The changes occur during washing due to the following actions:

Mechanical/rubbing/abrasion between garments to garments;

Garments to machine; and

Chemical action.

Garments washing is done due to the following reasons:

Washing process of garment is done to create wash look appearance. After

washing the garments create a new look which seems the new touch of

fashion.

By the washing technique, faded/old look, color or tinted effect is created in

the garments which also seems the best touch of garments.

The main and important function of washing is to reduce size materials as a

result the garment become size free and become soft hand feel.

When these soft garments are touched then it seems to best touch of

garments.

To attract the customers/Buyer by different types of Fashionable washing

and market developments.

Due to washing, shrinkage occurs in the garments. There is no possibility of

further shrinkage of the wash garments.

Any dirt, spot or germ if added in the garments during manufacturing is also

removed due to washing.

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TYPES OF WASHING:

Enzyme wash (Bio Polish wash & enzyme wash)

Stone Enzyme wash

Stone wash

Bleach wash

Sand Blasting

Permanent wrinkle

Normal wash/Garments wash

Pigment wash

Caustic wash

_____________

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Chapter-2

Enzyme:

Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions.

Like all catalysts, enzymes work by lowering the activation energy for a reaction

and thus dramatically accelerating the rate of the reaction. However, enzymes do

differ from most other catalysts by being much more specific. Enzymes are known

to catalyze about 4,000 biochemical reactions.

Enzymes are proteins produced by living organisms. All organisms produce a wide

range of enzymes to accomplish necessary biological tasks. Some enzymes can

also be replicated in the lab, or engineered to perform in a particular way. One of

the reasons that enzyme washing is so ecologically friendly is the natural origins of

enzymes, which biodegrade, rather than lingering in the water supply. Enzyme

washing products are also much more potent than other laundry products, requiring

people to use far less, in terms of volume.

Enzymes, like other proteins, consist of long chains of amino acids held together

by peptide bonds. They are present in all living cells, where they perform a vital

function by controlling the metabolic processes, whereby nutrients are converted

into energy and new cells.

Enzymes are biocatalyst, and by their mere presence, and without being consumed

in the process, enzymes can speed up chemical processes that would otherwise run

very slowly. After the reaction is complete, the enzyme is released again, ready to

start another reaction. In principle, this could go on forever, but in practically most

catalysts have a limited stability, and over a period of time they lose, their activity

and are not usable again. Generally, most enzymes are used only once and

discarded after; they have done their job.

Different types of enzymes are suitable for different stains. In all cases, the enzyme

washing process breaks the stain down into smaller molecules which can be

removed with water or conventional soap. Amylases will remove starch based

laundry stains, while proteases break down protein chains, making them suitable

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for protein stains. Lipases work very well on grease and oil, and cellulases are

excellent general cleaners. Enzyme washing also yields a softer, more supple

garment.

We have worked only with cellulose enzyme. We tried to know the effect of

cellulose enzyme on garments washing.

For delicate garments, enzyme washing can be an excellent way to get clothing

fresh and clean. Enzymes also work at very low temperatures, making them

suitable for cold wash only things ranging from silk to wet suits. Many natural

detergent products mix enzymes into their formulas, to ensure that they are

effective at all temperatures and on all stains.

http://www.wisegeek.com/what-is-silk.htm

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Etymology and history:

In 1878 German physiologist Wilhelm Kühne (1837–1900) coined the term

enzyme, which comes from Greek ενζυμον "in leaven", to describe this process.

The word enzyme was used later to refer to nonliving substances such as pepsin,

and the word ferment used to refer to chemical activity produced by living

organisms.

Enzymes are usually named according to the reaction they carry out. Typically the

suffix -ase is added to the name of the substrate (e.g., lactase is the enzyme that

cleaves lactose) or the type of reaction (e.g., DNA polymerase forms DNA

polymers).

Having shown that enzymes could function outside a living cell, the next

step was to determine their biochemical nature. Many early workers noted that

enzymatic activity was associated with proteins, but several scientists (such as

Nobel laureate Richard Willstätter) argued that proteins were merely carriers for

the true enzymes and that proteins per se were incapable of catalysis. However, in

1926, James B.

Sumner showed that the enzyme urease was a pure protein and crystallized

it; Sumner did likewise for the enzyme catalase in 1937 The conclusion that pure

proteins can be enzymes was definitively proved by Northrop and Stanley, who

worked on the digestive enzymes pepsin (1930), trypsin and chymotrypsin. These

three scientists were awarded the 1946 Nobel Prize in Chemistry.

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Enzymes are specific and work in mild conditions:

Enzymes can work at atmospheric pressure and in mild conditions with

respect to temperature and acidity (pH). Most enzymes function optimally at a

temperature of 30 -700C and at P

H values, which are near the neutral point (P

H 7).

Now-a-days, special enzymes have been developed that work at higher

temperatures for specific applications.

Enzyme processes are potentially energy saving and save investing in

special equipment resistant to heat, pressure or corrosion. Enzymes, due to their

efficiency, specific action, the mild conditions in which they work and their high

biodegradability, they are very well suited for a wide range of industrial

applications.

Enzymes are part of a sustainable environment:

Industrial enzymes can be produced in an ecologically sound way where the waste

sludge is recycled as fertilizer.

Enzymes and industrial applications:

Industrial enzymes are originated from microorganisms in the soil.

Microorganisms are usually bacteria, fungi or yeast. One microorganism contains

over 1,000 different enzymes. A long period of trial and error in the laboratory is

needed to isolate the best microorganism for producing a particular type of

enzyme. When the right microorganism has been found, it has to be modified so

that it is capable of producing the desired enzyme at high yields.

Enzymes for Textile:

There are a lot of enzymes like amylases, cellulases, catalase, pectinase and

protease for various textile wet-processing applications like desizing, bio-

polishing, denim finishing, bleach clean-up, bio-scouring and de-wooling.

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Sources of Enzymes:

According to Encyclopedia of Science & Technology (1992), industrial

enzymes are obtained from three major sources:

Plant: Malt diastase, papain, bromelain and ficin.

Animal: Pancreatic enzymes, pepsin, lipase, catalase, and rennin.

Microbial: Amylases, proteases, pectinases, invertase and glucose oxidase.

Enzymes are the products of living cells and like proteins; no enzyme has as

yet been successfully synthesized. Among many sources these are the most

common: animal tissues, organs and fluids such as muscle, liver and saliva; animal

products, such as milk and eggs; vegetable materials and a variety of seeds as

reported in Encyclopedia Americana (1967). Pancreatic enzymes are prepared

from slaughter house waste such as pancrease, clotted blood, liver etc.

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Different type of Enzymes:

Proteases:

Proteases are the most widely used enzymes in the detergent industry.

Proteases hydrolyze proteins and break them down into more soluble polypeptides

or free amino acids. As a result of the combined effect of surfactants and enzymes,

stubborn stains can be removed from fibres.

Lipases:

Though enzymes can easily digest protein stains, oily and fatty stains have

always been troublesome to remove. The trend towards lower washing

temperatures has made the removal of grease spots an even bigger problem. This

applies particularly to materials made up of a blend of cotton and polyester. The

lipase is capable of removing fatty stains such as fats, butter, salad oil, sauces and

the tough stains on collars and cuffs.

Amylases:

Amylases are used to remove residues of starch-based foods like potatoes,

spaghetti, custards, gravies and chocolate. This type of enzyme can be used in

laundry detergents as well as in dishwashing detergents.

Cellulases:

The development of detergent enzymes has mainly focused on enzymes

capable of removing stains. However, a cellulase enzyme has properties enabling it

to modify the structure of cellulose fibre on cotton and cotton blends. When it is

added to a detergent, it results into the following effects:

Colour brightening-When garments made of cotton or cotton blends have

been washed several times, they tend to get a 'fluffy' look and the colours become

duller. This effect is due to the formation of microfibrils that become partly

detached from the main fibres. The light falling on the garment is reflected back to

a greater extent giving the impression that the colour is duller. These fibrils,

however, can be degraded by the cellulase enzyme, restoring a smooth surface to

the fibre and restoring the garment to its original colour.

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Softening- The enzyme also has a significant softening effect on the fabric,

probably due to the removal of the microfibrils.

Soil removal- Some dirt particles are trapped in the network of microfibrils and

are released when the microfibrils are removed by the cellulase enzyme.

Structure:

The precise properties of cellulases vary depending on their origin. The

majority of microbial cellulases studied have been shown to be acidic proteins with

a significant carbohydrate content.

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Stability and storage:

The activity of cellulase preparations has been found to be completely

destroyed after 10-15 minutes at 80 °C. Solutions of cellulase at pH 5-7 are stable

for 24 hours at 4 °C. These products should be stored at 4 °C, in a dry place in

tightly closed containers. If stored in this manner, lyophilized preparation is stable

for several months without significant loss of activity.

Types of Machines used in Garments Washing Plant:

Sample washing Machine (Horizontal / Vertical Type)

Washing Machine (Side loading)

Washing Machine (Front loading)

Hydro extractor Machine

Dryer Machine (Steam)

Dryer Machine (Gas)

Chemical Mixture Machine

Industrial Oven (Gas/Electric/ Steam)

Boiler

Submersible Pump

Steam chamber for crinkle

E.T.P (Effluent Treatment Plant)

Generator

Sand Blasting Gun

Sand Blasting chamber

Spray gun and dummy

Compressor

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Sample washing Machine (Horizontal):

Washing Machine (Side loading):

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Washing Machine (Front loading):

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Hydro extractor Machine:

Dryer Machine (Steam)

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Dryer Machine (Gas):

Chemical Mixture Machine:

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Boiler:

Generator:

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Compressor:

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CELLULASE WASH:

Cellulase enzymes are natural proteins which are used in denim garment

processing to get stone wash look on to the denim garments without using stones

or by reducing the use of pumice stone. Cellulase attacks primarily on the surface

of the cellulose fibre, leaving the interior of the fibre as it is, by removing the

indigo present in the surface layer of fibre. These enzymes are different from the

alpha amylase enzymes used for starch removal in that they are selective only to the

cellulose and will not degrade starch. Under certain conditions, their ability to react

with cellulose (cotton) will result in surface fiber removal (weight loss). This will give

the garments a washed appearance and soft hand.

There are different forms and types of cellulase enzymes used in Bangladesh.

– One is Acid Enzyme (liquid) and another is Neutral Enzyme.

– Neutral Enzyme is two types - a) Powder form, b) Liquid form i.e., SL

Enzyme

Acid stable Enzyme:

– Acid enzyme is slightly brown in color.

– PH range is 4.5 to 5.5 during washing.

– Temperature : 40°c - 55°c.

– Time required : 20 to 60 mins.

– Enzyme effects come within short time.

– Staining/Bleeding occurs more on garments.

– Production high

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Neutral stable Enzyme:

– Found in powder form.

– Enzyme is slightly white powder form.

– PH range is 6 to 7 during washing.



– Enzyme effects come slowly.

– Less staining/bleeding on garments.

– With pumice stone give good effect/abrasion on garments.

– In dark shade enzyme effect is good.

SL ENZYME:

– SL enzyme is liquid form.

– PH range is 6 to 7.



– Enzyme effects come slowly.

– Less staining/bleeding on garments.

– With pumice stone the effect is better.

– For dark shade enzyme effect is good.

Alkaline stable(not used widely)

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Denim fabric is constructed of indigo dyed cotton warp yarns and natural

undyed cotton filling yarns. The warp yarns are dyed by a special process that

deposits the dye on the surface of the yarn, facilitating easy removal of the dye for

a wash down appearance.

The consumer can achieve this washdown appearance over time as a

garment is repeatedly worn and washed, or it can be achieved immediately by

cellulase enzyme treatment. In recent years, supplier variations in the composition

of cellulase have provided more effective cellulases, reduced back-staining

(redeposited indigo dye on the backside) of denim, reduced strength loss, and an

expanded range of optimum processing conditions.

Other types of fabrics, including lighter weight fabrics, can be cellulase

enzyme treated to achieve a cleaner, smoother surface by removing surface cotton

fibers. This effect will remain evident even after multiple home launderings.

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CELLULASE ENZYME PROCESSING:

A number of factors impact cellulase activity during processing, and these factors

can be classified as mechanical or chemical:

To optimize the application of cellulase to fabrics or garments, consideration

must be given to how these individual factors will collectively retard or accelerate

cellulase activity. Mechanical action varies from machine to machine, depending

upon the type and design. Most fabrics are processed in jets, jigs, or high-speed

air-tumbling units for surface modifications.

Overflow jets provide low mechanical action, requiring use of the more

aggressive, standard acid cellulase. Soft-flow jets deliver more mechanical action,

so either the modified acid or standard acid cellulase could be used. With the

higher mechanical action present in the high-pressure jets or air-tumbling units,

any one of the cellulases could be used.

Garments are enzyme processed in rotary drum or paddle machines,

typically used for garment washing and dyeing. The mechanical action of the

garments in these machines, including garment-to-garment abrasion, further

enhances surface fiber removal, color washdown, and softness.

Process times for cellulase treatment typically range from 0.5-2.0 hours. Delicate,

lightweight fabrics/garments are processed for shorter time periods.

MECHANICAL CHEMICAL

Equipment Type Cellulase Type

Equipment Design Cellulase Amount

Process Time Process Time

Garments wt. Process Temperature

Liquor Ratio Process PH

Machine Speed Auxiliary Chemicals

Auxiliary Products Pre-treatments

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When carefully controlled, the desired surface modifications can be

achieved within 30 minutes, without excessive strength loss. Heavier fabrics, such

as denim, normally require longer processing times at specific cellulase

concentrations to achieve the standard washdown of color reduction, seam

abrasion, and softness. Back staining of indigo denim is usually resolved by

switching from standard acid to modified acid or neutral cellulase.

Other options to reduce back staining include the use of anti-redeposition

agents, balancing enzyme amount/time factors, or reducing the load size.

Temperature control throughout the cellulase enzyme cycle is important for both

quality control and reproducibility.

Due to the narrow temperature range (normally 45-600C) for optimum

cellulase utilization, most operations choose to run the procedure at just below the

maximum temperature of 600C. Further reduction in temperature may be

employed when lightweight fabrics are treated or when the cycle time is extended.

Sometimes, lowering the reaction temperature will broaden the effective PH range,

an attractive strategy when ideal conditions are not achievable. As with

temperature, PH level affects cellulase performance.

For each cellulase type, an optimum PH exists where activity is maximized.

Precise control is difficult due to the many inherent variables, but operating within

a realistic range is crucial for quality control and reproducibility. A buffer system

of phosphate, citrate, or acetate is recommended to maintain PH during the entire

cycle due to the typical release of alkalinity from garments during processing.

Most textile operations process knit and woven fabrics at a 10:1 ratio of cellulase

solution to fabric, while garments are treated at lower ratios of 5:1. Often times,

lower ratios require less cellulase usage, but care must be taken to achieve uniform

results.

Often overlooked auxiliary chemicals can have a dramatic impact on the

activity of cellulase. Strongly ionic substances reduce cellulase activity. Generally,

nonionic surfactants tend to boost enzyme activity. Dyestuffs and fabric finishes

may have an impact on cellulase enzyme activity, and allowances should be made

for their effects. Vat dyes generally do not inhibit cellulase activity, but pigments

bound with film-forming acrylics will block cellulase access, therefore extended

time may be needed for acceptable washdown. Direct dyes, particularly those after

treated with fixing agents, and reactive dyes inhibit cellulase activity. Fabric

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finishes, such as finishes for wrinkle resistance, reduce the effectiveness of

cellulase by limiting accessibility to the internal fiber structure. However, a large

number of wrinkle-resistant garments are being successfully post-washed with

cellulase.

Process Sequences of Enzyme Wash (For Dark Shade):

The enzyme washing process of a batch of 60 kg denim men's long pant

(Trouser) are described below:

First Step :

DESIZING:

– Weight (80 pcs) : 60 kg

– Add water @ M : L = 1 : 9 : 540 Litre

– Machine Running

– Temperature : 60°c.

– Add Desizing agent @ 0.6 g/l : 324 gm.

– Add Detergent @ 0.8 g/l : 432 gm.

– Time : 10- 15 mins.

– Drop the liquor

– Wash 1 time by cold water

Second Step :

Enzyme Wash:

– Add water @ M : L = 1 :8 : 450 Litre


– Add Acetic Acid @ 0.3 g/l : 135 CC.

– Add Anti Back staining @ 0.6 g/l : 270 gm.

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– Add Enzyme @ 2.0 g/l : 900 gm.

– Time (Depend upon the shade) : 40- 80 mins.

– Drain the liquor.

– Increase temperature to 90°c and run 1 minute (for enzyme killing).

– Drain the bath.

– Rinse Twice, each 3 to 5 minutes

Third Step :

SOFTENING:

– Add water @ M : L = 1 : 8 : 450 Litre.

– Add Acetic Acid @ 0.6 g/l : 270 gm.

– Cationic Softener @ 1 g/l : 450 gm.

– Temperature : Room.

– Time : 10 to 15 mins.

– Drain the bath

– Then unload the garments on trolley.

Fourth Step :

Hydro-extractor Machine:

– After unloading garments from the washing machine then they are

sent to hydro-extractor machine to remove excess water from the

washed garments

Fifth Step:

Drying Machine:

– Load 60 kg garments to gas dryer.

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– Temperature set at 75°c to 85°c.

– Run about 40 mins.

– After then run 10 mins in cold dryer.

– Sixth Step:

– After Complete drying, the garments are sent to quality Control

section for quality checking and good ones are ready for delivery.

Samples:

Raw Denim Enzyme Wash (Dark Shade)

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Raw Denim Enzyme washed

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Raw Denim Enzyme Washed

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Raw Denim Enzyme Washed denim (Dark shade)

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Raw Denim Enzyme washed Denim

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Raw Denim Enzyme Washed

45

Raw Denim Washed denim (Medium Shade)

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Medium shade Garments

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ENZYME WASH PROCESS (For Light Shade):

The enzyme washing process of a batch of 60 kgs denim men's long pant

(Trouser) are described below:

First Step :

Desizing :

– Lot weight (80 pcs) : 60 kg denim long pant.


– Machine Running.


– Add Desizing agent @ 0.6 g/l : 324 gm.

– Add Detergent @ 0.8 g/l : 432 gm.

– Time :15- 25 mins.

– Drop the liquor.

– Wash 1 time by cold water

Second Step :

Enzyme Wash

– Add water @ L : R = 1 : 8 : 450 Litre



– Add Anti Back staining @ 0.6 g/l : 270 gm.

– Add Acid Enzyme @ 2.0 g/l : 900 gm.

– Time (Depend on shade) : 35- 60 mins.

– Increase temperature to 90°c and run 1 minute (for enzyme killing).

– Drain the bath.

– Rinse Twice, 5 minutes for each

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Third Step :

Bleaching:


– Temperature : 50°c to 60°c .

– Add bleaching agent @ 20 g/l : 8400 gm.

– Add sodium bi carbonate @ 4 g/l : 1680 gm.

– Time (Depend on shade) : 12 to 20 mts.



Fourth Step :

Neutralization -1

- Add water @ M : L = 1 : 10 : 600 Litre


– Add sodium meta-bisulphite @ 2 g/l : 1200 gm.

– Time : 10-15 mins



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Fifth Step :

Second bleach:



– Add hydrogen peroxide @ 4 g/l : 1920 gm.

– Add caustic soda @ 1 g/l : 480 gm.

– Add detergent @ 1 g/l : 480 gm.

– Time : 10 mins.


– Rinse Twice, 3 minutes for each and Neutralization is needed for

Second time.

Sixth Step :

Softening:

– Add water @ M : L = 1 : 8 : 450 Litre.


– Cationic Softener @ 1 g/l : 450 gm.

– Temperature : Cold.


– Drain the bath.

– Then unload the garments on trolley.

– Seventh Step : Hydro-extractor Machine

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After unloading garments from the washing machine then they are sent to hydro-

extractor machine to remove excess water from the washed garments.

Eighth Step :

Drying Machine:

– Load 60 kg garments to Steam dryer.

– Temperature set at 60°c to 75°c.

– Run about 40 mins.

– Then run 10 mins in cold dryer.

Ninth Step :

After dryer garments are sent to quality section for quality checking and then

garments are ready for delivery

Light shade is produced by enzyme wash

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STONE ENZYME WASH:

Now in Bangladesh most of the Denim garment is required STONE

ENZYME WASH effect. It is most popular wash for Buyer. A process of stone

enzyme wash of 60 kg batch of Denim Long Pant as mentioned below :

Pumic stone used in stone wahing

First Step :

Pre-treatment:

Desizing

– Batch Weight : 60 kg

– Add water @ M : L = 1 : 9 : 540 litre.

– Start the machine.

– Temperature : 60°c

– Add desizing agent : 0.6 g/l : 324 gm.

– Add detergent/Antistain : 1 g/l : 540 gm.


– Drop the liquor

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Second Step :

Hot wash:



– Time : 5 mins

Third Step:

Stone Enzyme Wash:


– Add pumice stone @ ½ volume of garments.

– Add Enzyme @ 1.50 g/l : 720 gms.

– Add Acetic Acid @ 0.6 g/l : 288 gms.

– Add Anti stain agent @ 0.8 g/l : 384 gms.

– Temperature : 40°c to 50°c..

– Time (Depend on shade) : 60 to 70 mts.

– Then temperature raise to 90°c for 1 minute.


– Rinse Twice, each for 3 minutes.

– Then pumice stone out from washing machine

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Fourth Step :

Bleaching:

– Add water @ M : L = 1 : 8 : 480 litre

– Machine running.

– Add bleaching powder (k.c.i) @ 10 g/l : 4800 gms

– Add soda ash @ 5 gm/l : 2400 gms


– Time (Depend on shade) : 10-15 m

– Drop the liquor

– Rinse twice, each for 3 minutes

Fifth Step :

Neutralization:


– Add sodium meta-bisulphite @ 3 g/l : 1620 gms


– Time : 10- 12 m

– Drop the liquor

– Rinse for 5 minutes.

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Sixth Step :

Softening:


– Add Acetic Acid @ 0.6 g/l : 288 gms.

– Cationic softener @ 1 gm/l : 480 gms.

– Time : 5 mins.

– Drop the liquor

– Unload the garments on trolley.

– Seventh Step : Hydro-extraction

Hydro-extraction of the garments are done to remove excess water from the

washed garments.

Eighth Step :

Drying :

– Load 40 kg garments

– Set temperature at 75°c to 85°c.

– Run for 35 to 40 mins.

– Then run 10 minutes for cold dry.

– Ninth Step : Delivery

After inspection garments are ready for delivery.

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Enzyme Inactivation:

To prevent any damage of the fabric after the finishing operation it is very essential

that the reaction be terminated at the end of treatment by enzyme inactivation . If

the enzyme is not inactivated entirely then at the end of the reaction fibres get

damaged and even extreme cases total destruction of the material may result. The

enzyme inactivation is therefore of great importance from the technical point of

view.

There are two distinct process of termination of enzyme:

1) Hot treatment at 800C for 20 minutes.

2) By raising the pH to 11-12.

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Advantage of enzyme washing:

1. Soft handle and attractive clean appearance is obtained without severe

damage to the surface of yarn.

2. Inexpensive, low-grade fabric quality can be finished to a top quality

product by the removal of hairiness fluff and pills, etc.

3. Simple process handling and minimum effluent problem.

4. Better feel to touch and increased gloss or luster.

5. Prevents tendency of pilling after relatively short period of wear.

6. Can be applied on cellulose and its blend.

7. Due to mild condition of treatment process is less corrosive.

8. Fancy colour-flenced surface can be obtained without or a partial use of

stone.

9. More reproducible effect can be obtained.

10. It allows more loading of the garment into machines.

11. Environmental friendly treatment.

12. Less damage to seam edges and badges.

13. Wear and tear of equipment is minimum due to absence of stone.

14. Use of softener can be avoided or minimised.

15. Easy handling of floor and severs as messy sludge of stones does not

interfere.

16. Due to absence of stone, labour intensive operation of stone removal is not

required.

17. Homogenous abrasion of the garments.

18. Puckering effect can also be obtained.

19. Problem of pumice powder contamination on garment is not there.

Evaluation of the Fabric:

Evaluation of the denim fabric after treatment with enzyme is, to be effective in reduction of hairiness, impartation of softness, wash-down effect etc. The enzyme was active in reducing hairiness, backstaining, wash-down effect, and imparting softness to the fabric or garments.

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Bio-polishing of Knit Fabric:

Cotton and other natural and man-made cellulosic fibers develop pills or

protruding fibers during spinning, weaving and wet processing operations, due to

abrasions. These pills make the appearance of the yarn or fabric to be dull and

hazy. In order to improve the appearance it is necessary to either remove the

protruding fibers or to cement it to the surface properly by the application of some

over coating.

Cotton and other natural and man-made cellulosic fibers can be improved by

an enzymatic treatment called Bio-Polishing. The main advantage of Bio-Polishing

is the prevention of pilling.

Enzyme cellulases hydrolyze the micro fibrils (hairs or fuzz or pills)

protruding from the surface of yarn because they are most susceptible to enzymatic

attack. This weakens the micro fibrils, which tend to break off from the main body

of the fiber and leave a smoother yarn surface.

After Bio-Polishing, the fabric shows a much lower pilling tendency. Other

benefits of removing fuzz are a softer, smoother feel and superior brightness of the

dyed shade or white. Unlike conventional softeners, which tend to be washed out

and often result in a greasy feel, the softness-enhancing effects of Bio-Polishing

are wash proof and non-greasy.

For cotton fabrics, the use of Bio-Polishing is optional for upgrading the fabric.

However, Bio-Polishing is almost essential for the new polynosic fiber lyocell.

Lyocell is made from wood pulp and is characterized by a tendency to fibrillate

easily when wet. In simple terms, fibrils on the surface of the fiber peel up. If they

are not removed, finished garments made with lyocell will end up covered in pills.

This is the reason why lyocell fabric is treated with cellulases during finishing.

Cellulases also enhance the attractive, silky appearance of lyocell.

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Bio-Polishing has a lasting effect on knitted as well as woven fabrics, giving

improved resistance to pilling, a clearer, lint-free and fuzzless surface structure,

and improved drapability and softness.

Cellulase enzyme is used for bio-polishing of cellulosic fabric under acidic

conditions. It partially digests excess and protruding yarns, loosening them from

the fabric. The resulting fuzz is then easily removed by mechanical agitation of the

fabric. This not only creates a smoother fabric with resistance to pilling, but also

improves softness, luster and drape.

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Mechanism of Biofinishing:

Understanding the behavior of the cellulolytic enzymes towards the cotton

fiber is essential to minimize the related negative effect on the strength of the

cotton fabric. Cellulose is made up of highly ordered crystalline region and less

structured amorphous region. The degree of departure from crystallinity is variable

to form the less structured purely amorphous region with all degrees of order in

between. The amorphous region is generally responsible to form the fuzz and

pilling in cotton fabric. Hence, a single type of cellulose preferentially

endoglucanase may probably be sufficient for degradation of amorphous cellulose

with minimum weight loss.

There is also evidence that during biosynthesis of cellulose the associated

hemicelluloses regulate the aggregation process. Thus, application of cellulase for

biofinishing along with xylanases may probably have an added advantage mainly

in removal of the surface fibrils, small protruding fibers, seed coat fragments, and

other natural impurities of cotton fiber. Use of xylanase along with cellulase in

optimum concentration at suitable conditions for enzymatic action will prove to be

beneficial with minimum harm to the fabric during biofinishing. We represent here

a schematic diagram that indicates the probable mechanism of enzymatic

finishing and stone washing of denim garment by endoglucanase Fig. During

indigo staining of denim garment the indigo dye particles get adhered to the

microfibrils that are present on the surface of the garment (Fig. b). Endoglucanase

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acts on the amorphous region of the cellulose forming the protruding hairs

on the fabric generally responsible for causing fuzz and pilling on the fabric as

seen in the scanning electron micrograph and loosens it.

The mechanical action in the washing machine in turn removes the loosened

fibers to give a final finished product (Figs. d and b). Also as the protruding fibers

are removed the indigo particles adhering to the surface of the protruding fibers are

also removed thus giving the fabric a patchy appearance which is preferred (Fig.

d).

Xylanases will act on the seed coat fragments and other natural impurities

thus giving a final finished touch to the cotton fabric.

Cellulases are also used to improve the appearance of cellulosic fabrics by

removing fuzz fiber and pills from the surface, reducing pilling propensity, or

delivering softening benefits.

Since cellulose is made up of highly ordered crystalline region and less

structured amorphous region, a single type of cellulase preferentially

endoglucanase will be sufficient for degradation of amorphous cellulose

causing fuzz and piling of the fabric.

Treatment of cotton fabric with cellulases along with an appropriate dose of

xylanase will help in removal of seed coat fragments and other natural impurities

of cotton.

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Bio-Polishing of knit fabric with Cellulase Enzyme:

In the recent years enzymes have found a variety of uses in textile

applications. Popular uses are stone washing of denims and surface modification of

cellulosic fabrics to improve their appearance and handle. The process of treating

with cellulases is termed as bio-polishing. In case of denims one can get stone-

wash effect without using pumice stones by using enzymes. Another advantage of

using enzymes is that, these are environment friendly, since they are readily

biodegradable.

Besides, they will not leave chemical residue on the processed materials and the

colour changes on the dyed goods are very less.

Knitted goods treated with enzymes are free from surface hairiness and neps with

much improved handle and flexibility. The fabric surface becomes smoother and

more lustrous. There is also a lower tendency to further pilling possibly due to the

fact that there are less protruding fibre ends from the yarns after the enzyme

application.

Bio-finishing also called bio-polishing, is a finishing process applied to cellulose

textiles that produces permanent effects by the use of enzymes. Bio-finishing

removes protruding fibres and slubs from fabrics, significantly reduces pilling,

softens fabric hand and provides a smooth fabric appearance, especially for

knitwear and as a pretreatment for printing.

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Favorable conditions of enzyme for Bio-finishing:

More than with other chemical reactions, the enzyme catalysed hydrolysis of

cellulose is strongly influenced by factors such as pH, temperature, time and

agitation. The optimal pH for a particular cellulase depends upon its origin.

Enzymes are more effective at pH 6 - 6.5. The reaction temperature is also

critical since at low temperatures, the reaction rate is slower than desired, but very

high temperature can deactivate the enzyme by providing enough energy to alter its

molecular alignments and thereby destroy its catalystic ability.

Since enzymes are true catalysts and are not consumed during the chemical

reaction, the hydrolysis reaction will continue until either the reaction conditions

change or the cellulose is physically removed from the reaction mixture.

Because the enzyme’s catalytic action is not reduced during the reaction,

effective methods of ending the hydrolysis must be employed to prevent excessive

fibre loss.

Since the molecule’s physical alignments are crucial to its catalytic ability,

procedures that alter the cellulase molecule’s internal structure can be used to

deactivate the catalysis and halt the hydrolysis. High temperatures (> 700C or

1600F for at least 20 min or short drying at 120

0C or 248

0F), high P

H (>10) and

high electrolyte content as well as enzyme poisons can serve to terminate the

reaction by distorting the enzyme’s molecular shape.

Recipe for Bio-finishing of knit fabric:

Neutral Cellulase Enzyme - 1% owf

PH

- 5-6.5

Time - 1 hour

Temperature - 55◦C

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Procedure of bio-polishing of Knit Fabric:

• Load the fabric or garment in the machine • Fill the machine with water

• Add nonionic wetting agents (0.2 to 0.3 gpl)

• Adjust pH 4.5 to 5.5 with acetic acid

• Add 2 gpl lubricant (non-ionic)

• Run the machine for 30 minutes at 50-60 ◦C

• Remove one garment from the machine and compare with the unwashed garment

to see the effect of bio-polishing

• If bio-polishing is satisfactory, raise the temperature gradually to 85◦C and

maintain the temperature for 10 minutes to deactivate the enzyme

• Drain the liquor

• Cold rinse for 5-10 minutes followed by hydro extraction and tumble dry.

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Process sequences of Bio-finishing:

Scouring & Bleaching

Neutralization

Enzyme process

Dyeing

After Treatment

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Samples:

Raw Fabric Bio-polished Fabric

Recipe:

Acid Cellulase- 0.8% owf

PH- 4-5.5

Time- 50-70 Minutes

Temperature- 55◦C

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Raw sample Bio-Polished sample (50 minutes)

Polished sample (70 minutes)

Recipe:

Acid Cellulase- 1% owf

PH- 4-5.5

Temperature- 55◦C

Time- 50-70 minutes.

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Raw Fabric Polished Fabric(1%)

Polished Fabric (1.5%)

Recipe:

Acid Cellulase- 1-1.5% owf

PH- 4-5.5

Temperature- 55◦C

Time- 50minutes.

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Advantages of using enzymes for bio-polishing are:

• Hairiness, fluffs and pills are removed.

• Material sticking (the burr effect) is prevented.

• Improved handle.

• Achievement of surface smoothness and a clear structural appearance.

• Improved lustre.

• Material texture relaxation.

• Increased flexibility and therefore a soft handle even with over end-

products and mercerized fabric.

• Improved sewability.

• Fast to washing, low pilling tendency, no napping in use, or during

care operation.

• Lustrous, soft, top quality with a fine, high quality surface appearance.

Provides surface polishing and softening.

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Cellulase enzyme offers the following benefits:

Specific action on protruding fibers only.

Improves texture, softness and appearance of fabric.

Wide variety of application processes.

Eco-friendly & Biodegradable.

No damage to strength of fabric.

Disadvantages of this finishing technique:

• Loss in weight

• Loss in strength

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Testing & Analysis:

The following tests can be carried out to assess the properties of bio-polished

cotton knitted fabric.

i) Wash fastness , ii) Abrasion resistance, iii) Weight loss, iv) Pilling.

Requirement of Enzyme Wash:

Now we can say Enzyme wash is required for the following reasons:

– To remove the size materials from the garments.

– To remove the starch presents on the garments fabrics.

– To achieve the high low abrasion (stone effect) on garment and seam

abrasion in sewing area.

– Enzyme attack as chemically not mechanically for this reason low

damage/wastage than stone wash.

– For soft feeling to wear the garment.

– To achieve the buyer required sample.

– To increase the color fastness & rubbing fastness.

– Especially develop the "Bio-Polishing" effect of cotton/denim.

– Enzyme improves the anti-pilling properties.

– Enzyme attacks more the surface of the fabrics and gives a very

smooth surface

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Conclusion:

The most attractive feature of denim fabric is its washing effect. This is produced by mechanical and chemical processing. The entire processes gives rise to the wastage hence effluent and environment is polluting at a large scale. Enzyme technology provides an environment friendly process to obtain the desired effect. The bio-polishing of knit fabric can also be done with cellulase enzyme which removes the protruding fibres of the fabric and gives a smoother, softer, Brighter and cleaner fabric. The activity of the Enzyme can be controlled easily by maintaining the P

H, Temperature, Concentration and time.

The enzyme washing and Bio-polishing provides a better and uniform effect

over the conventional processes. Though the enzymes are costly but it is energy and time saving over the conventional processes. The limitation of Enzyme washing is that when localized washing effect is needed it is difficult to produce it. In the future, enzyme technology will continue in importance as biochemists and textile chemists strive to create new product and processing innovations to further revolutionize textile processing.

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application of cellulase enzyeme in textile processing by shaikh

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